Effects of heating and hydraulic cycling on the stiffness response of a rigid ansiotropic clay: preliminary results
Tipus de documentComunicació de congrés
Condicions d'accésAccés obert
The poster presents the results of an experimental investigation aimed at evaluating the effects of heating and hydraulic cycling on the small-strain stiffness of a rigid Jurassic clay (Opalinus clay, Jura Mountains, Mont Terri Underground Laboratory, Switzerland). This clay was subjected to thermal loads during an in situ heating experiment (HE-D). After the test, intact samples were retrieved and analysed at laboratory scale. The influence of thermal loads was studied using basic characterisation, microstructural techniques (MIP) and non-destructive techniques (ultrasonic pulses). The retrieved samples were then subjected to wetting and drying paths. The hydraulic effects were tracked using basic characterisation (water content and porosity) and non-destructive techniques (ultrasonic pulses and bender elements). Test results showed a higher sensitivity of stiffness on suction increase for the material less affected by the thermal load (far from heater). Tests are currently being carried out on a new and fully instrumented high-pressure triaxial cell to monitor degradation effects induced by hydraulic cycling under a controlled stress field. Degradation is monitored by horizontal and vertical bender elements to track different directions.
CitacióMitaritonna, G. [et al.]. Effects of heating and hydraulic cycling on the stiffness response of a rigid ansiotropic clay: preliminary results. A: Deformation and failure of geomaterials. A Multidisciplinary Scientific Workshop. "Deformation and failure of geomaterials. A Multidisciplinary Scientific Workshop". Brindisi: 2009.